Polymeric compound

ABSTRACT

A polymer compound which is a polyphenylene co-condensation polymer consisting substantially of paraphenylene group and metaphenylene group and improved in forming ability and functions, wherein the ratio of metaphenylene group is in the range of 60 to 95%.

FIELD OF THE INVENTION

The present invention relates to unsubstituted polyphenylene polymermaterials which is soluble in organic solvent, have heat-resistance andluminescence, have photo.electron function and can be a carbonizingmaterials.

BACKGROUND OF THE INVENTION

Up to the present, polyparaphenylene having a structure of followingcompound 1,

(n is a repeating unit number) is well known as a compound which hasheat-resistance and displays electric conductivity by adding anoxidizing agent (electron acceptor) and a reducing agent (electrondonor) [refer to Synthetic Metals, Vol.1. p307(1979), Kyoritsu Shuppan“Electric conductive polymer” p4 (1987), Kyoritsu Shuppan “Polymerbattery” p15 (1990)]. Further, in J. Phys. Chem. Vol.100, p12631 (1996),Advanced Materials, vol.4, p36 (1992) or in others, there is adescription that said polymer is a substance which displaysphotoluminescence. Still more, there are many reports disclosing thatsaid polymer is a substance which is electrochemically active showingelectrochromizm [J. Phys. Chem. Vol.100, p12631 (1996)] or disclosingthat said polymer can be a starting material to obtain a carbonizingmaterials by carbonization such as calcination [J. Mater. Res. Vol.13,p2023 (1998)].

Further, regarding the synthesis example of polymetaphenylene having astructure of compound 2,

(m is a repeating unit number) is already reported in Bull. Chem. Soc.Jpn., Vol. 51, p2091 (1973) and reports that said compound indicatesfluorescence.

While, the conventional method for preparation of polyphenylenes arementioned as follows.

As the method to obtain said polyparaphenylene or polymetaphenylene,there is a report relating a synthesis method using 1,4-2 substitutedbenzene or 1,3-2 substituted benzene as a starting material [a. JP Pat.Laid-Open Publication 52-154900, b. Bull, Chem, Soc. Jpn., Vol.51, p2091(1978), c. Macromol, Chem. Rapid Commun. Vol16, p761 (1987), d.Macromolecules, Vol.25, p1214 (1992), e. Makromol Chem. Phys., Vol. 198,p341 (1997)].

Examples of said method can be indicated by following schema 1 or schema2.

(wherein, X is halogen, M is reductive metal or metal compound such asMg, Zn or zero value nickel complex, n and m are same meaning tochemical formulae 1 and 2). This reaction is a method to dehalogenizingpolycondense the starting material by M (for example, MgX(2) isgenerated simultaneously) and the compound of nickel, palladium or ironare as a catalyst (refer to above mentioned documents a and b).

Further, a reaction which uses a reducing agent such as NaH orhydrazine, and uses a nickel compound or palladium as a catalyst,further uses a lower valency compound of nickel or palladium generatedby the reaction of the catalyst with said reducing agent as M in abovementioned schema 1 and 2 is already reported [refer to above mentioneddocument e, and f. Bull, Chem, Soc. Jpn., Vol. 72, p621(1999))].

In the case of dehalogenizing polymerization using above mentioned M,there is a conception that halogen is remaining at the end of polymer asshown in chemical formula 3,

or end group represented by chemical formula 4

is converted to chemical formula 5

by a reaction with methanol or water during a treatment process of apolymer compound, which is already reported too (refer to mentioneddocument b). Further, there is also a report disclosing that when thispolymerization reaction is carried out in tetrahydrofuran,oxysotetramethylene group generated by cleavaging reaction oftetrahydrofuran is took in into a polymer chain (refer to mentioneddocument b).

These end groups or the oxysotetramethylene group which is took in intoa polymer chain, it is not necessary to remove by after treatment, ifthey do not affect largely to the physical property such asheat-resistance or luminescence and to the use for the carbonization.The small taking in amount of oxysotetramethylene group, has rather goodeffect to improve the solubility of a polymer compound.

Still further, there is a report disclosing that a coupling reactionwhich uses a boron compound or a tin compound is usable as a synthesisof poly (arylene) such as polyparaphenylene (refer to mentioned documentf). In this method for polymerization, for example, the methods forpolymer synthesis according to following schemata 3, 4 and 5 can bementioned.

In above schemata, n is a repeating unit, and in above polymerizationmethods, a palladium compound can be added as a catalyst at need.Furthermore, in an ordinary reaction, it is possible to obtainpolyparaphenylene using 1,4-substututed benzene possessing an eliminablesubstitution group. Likewise, it is possible to obtain polyparaphenyleneusing 1,3-substututed benzene. Still more, when needs are arisen, it ispossible to carry out the polymerization reaction in the condition wheresmall amount of 2,5-dibromoprydine or 1,3,5-tribromobenzene are existingtogether with, and the unit originated to these halogen compounds can betook in into a polymer as a part.

However, said polyphenylene polymer has a problem of insoluble andinfusible because of it's rigid linear structure, further has a problemthat the application to a materials for photo.electron function isdifficult because of lacking of molding ability and excipiting ability.

The subject of the present invention is to obtain phenylene polymerwhich solve the problem of lack of molding ability.

For the purpose to accomplish the subject of the present invention,various trials are carried out, and among the trials to co-condense basematerials for conventional phenylene polymers by various blendingamount, the following fact is found out and the subject of the presentinvention is accomplished. That is, a polymer which contains 40-95 mol %of meta-phenylene unit, desirably a polymer which contains 60-90 mol %of meta-phenylene unit, more desirably a polymer which contains 80-90mol % of meta-phenylene unit has a characteristic to be soluble in anorganic solvent, which is an unexpected effect from a homopolymer.

DISCLOSURE OF THE INVENTION

The present invention is a polymer compound substantially comprising anunsubstituted paraphenylene group and an unsubstituted metaphenylenegroup, wherein the ratio of the metaphenylene group is in the limit of60-95%. Desirably, said polymer compound is soluble in organic solvent,more desirably, the molecular weight of said polymer compound is in thelimit of 600-40000.

BRIEF ILLUSTRATION OF THE DRAWINGS

FIG. 1 shows the infrared spectrum (transmittance %) of polymer whoseratio of paraphenylene and metaphenylene is 5:5 (in tables indicated byP5/5).

FIG. 2 shows the infrared spectrum (transmittance %) of polymer whoseratio of paraphenylene and metaphenylene is 3:7 (P3/7).

FIG. 3 shows the ¹H-NMR (in CDCl₃, 400 MHz) of polymer whose ratio ofparaphenylene and metaphenylene is 3:7 (P3/7).

FIG. 4 shows the ¹H-NMR (in CDCl₃, 400 MHz) of polymer whose ratio ofparaphenylene and metaphenylene is 1:9 (P1/9).

FIG. 5 shows the ultraviolet absorption spectrum polymers whose ratio ofparaphenylene and metaphenylene are respectively 1:9 (P1/9), 2:8(P2/8-3) and 3:7 (P3/7).

FIG. 6 shows the infrared spectrum of polymer whose ratio ofparaphenylene and metaphenylene is 2:8 and molecular weight is in Table3 is indicated as “P2/8-1”.

FIG. 7 shows the fluorescence characteristic of polymer whose ratio ofparaphenylene and metaphenylene is 2:8 and molecular weight is in Table3 is indicated as “P2/8-3”.

THE BEST EMBODYMENT TO CARRY OUT THE INVENTION

The present invention will be illustrated more in detail. A. Synthesisof the Polymer Compound of the Present Invention

The polymer compound of the present invention can be obtained based onthe method for synthesis of said paraphenylene and metaphenylene,namely, by polycondensation reaction using 1,4-substituted benzene and1,3-substituted benzene as the starting materials.

Substantially, for example, can be obtained by following schemata 6 and7 under the presence of catalyst.

(wherein, X is halogen, R is alkyl group and n and m are repeating unitnumber) In said reaction, it is possible to obtain a copolymer havingblocking ability by contriving the adding order of said two monomers.

There is no limitation in sequence of a paraphenylene group and ametaphenylene group in the polymer compound obtained as above, however,it is desirable that the polymer is to be a randomized copolymer becausethe lower crystallized polymer is advantageous for the purpose toimprove the solubility. Concretely, it can be accomplished byinvestigating adding order of monomers, reacting temperature and a kindof catalyst.

B. Since almost of the polymer compounds of the present invention aresoluble in organic compound, it can be applied to the conventionalmethod to produce various molded products such as film which usespolymer solution for a casting method or an extruding method of thesolution to a coagulation solution composed of poor solvent.

C. Usually, for the purpose to obtain a carbon material, in particular,to obtain a film shape carbon material which has high addition value, itis reported that it is necessary to adjust the physical property of thefilm to be provided to the carbonization.

Further, it is already known that the polymer compound characterizingthat the component which is lost during the carbonizing process, and notcontaining oxygen or sulfur which affects the carbonization process isdesirable. As the concrete example, the use of a film material formedfrom coal pitch or polyacrylonitrile is well known.

The characteristics of the polymer compound of the present inventionmeet to the mentioned requirement. That is, the polymer compound of thepresent invention has good efficiency to the carbonization and themolding from the solution is possible and the molding process is easy,therefore, the quality of the obtained film is excellent. Therefore, bythe carbonization of said film, it is expected that the film shapecarbon material can be obtained. The film shape carbon material isuseful as the electrode material for a secondary electrode.

D. Regarding the molecular weight of the polymer compound of the presentinvention, there is no limitation, however, it is desirable that themolecular weight is larger than 600 to obtain the intensity necessary tothe polymer compound of the present invention.

E. The polymer compound of the present invention is usable as thepolymer to form a charge-transfer complex as well as polyparaphenyleneor polymetaphenylene material having characteristics of an electricconductive organic polymer as an electron donor which composes acharge-transfer complex to obtain an organic semiconductor or organiccharge-transfer material by combining with various electron acceptorsuch as tetracyanoquinodimethane, tetracyanoethylene or iodide.

F. Further, the polymer compound of the present invention can observefluorescence characteristic at the region from soft ultraviolet to shortwave length visible light (blue region) by irradiation of ultravioletray, and is useful as a fluorescence material.

Example 1

The reaction between mixture of paradibromobenzene andmetadibromobenzene (total amount is 5.9 g, 25 mmol) with magnesium (0.61g, 25 mmol) is carried out in tetrahydrofuran anhydride (35 mL) underargon gas flow at the room temperature.

The reaction in tetrahydrofuran is continued for 2 hours, and magnesiumis vanished. Br—C₆H₄MgBr—p, Br—C₆H₄MgBr—m, p—C₆H₄(MgBr)₂, m—C₆H₄(MgBr)₂are considered to be generated at this time (refer to mentioned documentb).

Then, dichloro(2,2′-bipyridine) nickel (II) (25 mg, 0.087 mmol) is addedto said tetrahydrofuran solution as a polymerization catalyst,polymerized at the room temperature for 1 hour further, polymerizated atthe temperature of 75° C. under argon gas flow, and the reactingsolution containing polymer compound is obtained. Said recting solutionis poured into 250 mL ethanol with constant stirring and the precipitateis recovered by filtration. The obtained powder is rinsed by dilutehydrochloric acid, water and ethanol, dried by a vacuum desiccator andthe copolymer is obtained.

Said method for polymerization is in accordance with the method forsynthesis of paraphenylene which is already reported (refer to mentioneddocuments a and b).

By said method, the copolymer mentioned in Table 1 is obtained. As theComparative Example, polyparaphenylene (PPP) and polymetaphenylene (PMP)obtained by same method are also summarized in Table 1.

TABLE 1 Polymer Polymerization compound a P:M b time c Yield (%) PPP10:0  4 97 P6/4 6:4 4 76 P5/5 5:5 4 64 P4/6 4:6 4 61 P3/7 3:7 24 56P2/8-1 2:8 4 39 P2/8-2 2:8 10 38 P2/8-3 2:8 24 67 P2/8-4 2:8 40 67 P1/91:9 24 50 PMP  0:10 4 49 a: abbreviation of the obtained polymercompound b: material monomer c: reaction time at 75° C. P = p-C₆H₄Br₂, M= m-C₆H₄Br₂ PPP = polyparaphenylene PMP = polymetaphenyleneIn Table 1,

Characteristics of Polymer:

The IR spectrum of PPP obtained by the method disclosed in document b,has a strong absorption at 1000 cm⁻¹ which is originated to theparaphenylene group (considered mainly caused by in-plane deformationvibration). The IR spectrum of PMP obtained by the method disclosed indocument b, has a strong absorption at 1595 cm⁻¹ which is originated tothe metaphenylene group (considered mainly caused by cyclic vibration).Further, it become clear from the intensity of the absorption, the ratioof mole absorption modulus of absorption by the paraphenylene group ofapproximately 1000 cm⁻¹ and absorption by the metaphenylene group ofapproximately 1595 cm⁻¹ is about 1:1.

All of the IR spectrums of copolymers shown in Table 1 of the presentinvention display two absorptions at 1000 cm⁻¹ and 1595 cm⁻¹ which arecharacterized to a paraphenylene group and a metaphenylene group,therefore it clearly indicates that the polymer compound is a copolymer.

Assuming the ratio of molar absorption coefficient by a paraphenylenegroup and a metaphenylene group of said PPP and PMP can be applied to acopolymer, the ratio of paraphenylene group:metaphenylene group obtainedfrom the IR spectrum (FIGS. 1 and 2) of copolymers of P5/5 and P3/7 inTable 1 are 55:45 and 65:35. Concerning the accuracy of IR analysis,therefore, it becomes clear that paradibromobenzene andmetadibromobenzene display almost same reactivity at polymerization.

While the specimen for IR spectrum shown in FIG. 2 partially containssilicone grease and shows absorption at 1260 cm⁻¹.

¹H-NMR (400 MHz in CDCl₃) spectrums of Table 1 are shown in Tables 3 and4. The sharp absorption of δ 7.26 is based on CHCl₃ impurity in CDCl₃.Further, a particular absorption pattern of an aromatic hydrocarboncompound containing more than two kinds of paraphenylene group ormetaphenylene group at δ 7.3-8.0 (for example, 206M, 1613M, 5083M, 661Mspectrum of ¹H-NMR date book) is shown. By the comparison with ¹H-NMRspectrum of various aromatic hydrocarbon compounds (for example, thespectrum in said ¹H-NMR date book), the absorption of approximately δ7.7-8.0 can be guessed to be depended on isolated C—H bond ofmetaphenylene group, however, since the absorption pattern is verycomplicated, the sufficient component analysis was impossible.

Every polymer compounds in Table 1 are stable till 300° C. inthermogravimetric analysis under nitrogen gas flow. Further, at 850° C.,the residue weight of these polymer compounds are approximately 50%.Still further, these polymer compounds becomes black at 850° C., and itis confirmed that these polymer compounds are carbonized.

In FIG. 5, ultraviolet-visible light absorption spectrums of P1/9,P2/8-3, P3/7 (a, b, c) are shown. The ratio of paraphenylene group isincreasing by a, b, c order the large unit whose effective π conjugatedchain increases and it is clear that the absorption of 280-320nm aroundis increasing.

Example 2

The solubility of synthesized copolymers to various solvents are shownin Table 2.

TABLE 2 Polymer compound: solvent THF DMF DMSO CHCl₃ PPP X X X X P9/1 XX X X P8/2 X X X X P7/3 X X X X P6/4 X X X X P5/5 X X X X P4/6 Δ Δ Δ XP3/7 Δ Δ Δ ◯ P2/8 ◯ ◯ ◯ ◯ P1/9 ◯ ◯ ◯ ◯ PMP X X X X X: insoluble, Δ:partially soluble, mostly suspended, ◯: soluble (solubility test: 10mg/mL) From P2/8 to P2/8-4 show same solubility. In the Table, THF:tetrahydrofuran, DMF: dimethylformamide, DMSO: dimethyl sulfoxideInfrared spectrum of P2/8-1 is shown in FIG. 6.It is understood that the polymer containing 40-91 mol % ofmetaphenylene unit, further, the polymer containing 80-90 mol % ofmetaphenylene unit is superior in solubility.

The preparation of film is carried out by casting THF solution orchloroform solution on a glass substrate and by air drying THF orchloroform. The obtained film is a smooth and transparent film.

While, since the polymer compound obtained by the polymerization ofExample 1 have possibility to remain a parabromophenyl group or ametabromephenyl group at the end [refer to above mentioned document aand b, and same subject is also reported in Macromolecules vol. 28,p4577 (1995)], the polymer compound is dispersed in tetrahydrofuran andtreated by LiAlH₄, and the polymer compound not containing bromine isobtained.

End treatment of the obtained polymer and the characteristics of it. Forexample, P2/8-2 and P2/8-4 are reacted with LiAlH₄ and debrominated asshown in following schemata 8 and 9,

and debrominated polymer (indicated by P2/8-2-H, P2/8-4-H) are obtained.

And the elemental analysis value of P2/8-2-H is carbon: 89.87% andhydrogen: 5.75%, while that of P2/8-4-H is carbon: 93.02% and hydrogen:5.75%. The mole ratio of each polymer compounds are approximatelycoincidental with the calculated value as polyphenylene. The reason whythe analytical value of carbon in P2/8-2-H is slightly lower than thecalculated value when infinite chain length polyphenylene is assumed(carbon: 94.70%, hydrogen: 5.30%) can be considered to be caused byflame retardancy, partially contained water and mixing of small amountof inorganic compound. Since P2/8-2-H and P2/8-4-H obtained as aboverelatively shows same solubility to the original polymer compound P2/8-2and P2/8-4, it becomes clear that the end bromine does not give anyeffect to the solubility.

Example 3

Molecular Weight of Polymer

Regarding the polymer compound which displays DMF solubility, numberaveraged molecular weight (hereinafter shortened to Mn) and weightaveraged molecular weight (hereinafter shortened to Mw) are measuredaccording to a gel permeation chromatography (GPC) method. For themeasurement, HLC-8120GPC, which is a product of TOSO Co., Ltd. is used,as a detector UV-8020 (detecting wave length is 300 nm) is used and DMFwhich contains 0.006M LiBr is used as a developing solvent. As theresults, Mn and Mw of Table 3 by polystyrene conversion are obtained.

TABLE 3 Molecular weight of polymer compound Polymer compound Mn MwP2/8-1 1270 2150 P2/8-2 1310 2000 P2/8-3 2590 2980 P2/8-4 2300 2780P2/8-2-H 1330 2040 P1/9 1290 2980

The GPC curve of P2/8-1 and P2/8-4 are relatively showing thedistribution of molecular weight 230-17500 and 660-7310 and indicatesthat the polymer compounds of this region are soluble in DMF.

Example 4

Fluorescence Characteristics of Copolymer

Copolymer P2/8-3 is dissolved in chloroform and cast on anon-fluorescent glass plate, the solvent is removed and the film ofP2/8-3 is obtained. The fluorescence of the film is measured, and theresult shows that the film indicates strong fluorescent having aluminous maximum at 432 nm (FIG. 7). And it becomes clear that theexcitation spectrum of it shows the peak at 350 nm. Still more, itbecome clear that the polymer compound of Table 1 indicates fluorescentin solid and solution condition under the irradiation of ultra violetray.

The fluorescent spectrum of P3/7 in THF solution has a fluorescent peakat 370 nm around and the excitation spectrum shows the peak at 250nm-300 nm around.

Fluorescence Characteristics of Vacuum Deposition Film

PPP, P6/4, P5/5, P4/6, P2/8-1 and PMP are vacuum deposited on a quartzglass plate and a thin film is formed.

The fluorescent intensity of these thin films are compared, and therelative intensive ration is 1:5.5:7:7:1:0.5. From this result, itbecomes clear that the isolated copolymer of paraphenylene andmetaphenylene shows strong fluorescence, that is, the characteristicwhich is particular to a copolymer.

Example 5

Paradibromobenzene (1.18 g, 5.0 mmol) and metadibromobenzene (4.72 g, 20mmol) are reacted with 0.61 g (25 mmol) of magnesium in the mixedsolution of tetrahydrofuran anhydride (10 mL) and dibutyl ether (50 mL)under the argon gas flow. By refluxing, reacted for 12 hours, and aftermagnesium is disappeared, dichloro(2,2-bipyridine)nickel(II) (25 mg) isadded as a catalyst. The polymerization reaction is carried out byrefluxing condition under argon gas flow for 5 hours, then the generatedpolymer compound is recovered by same method to the Example 1. The yieldis 720 mg (yield % is 38%). The reason why the yield % is low, isconsidered because a part of polymer is soluble in ethanol. Said polymercompound is soluble in N,N′-dimethylformamide, chloroform andtetrahydrofuran and 0.2 g/dL N,N-dimethylformamide solution indicates0.10 dLg⁻¹ η sp/c (η sp=specific viscosity). And the chloroform solutionof polymer compound indicates fluorescent having peaks at 356 nm and 372nm under the irradiation of 260 nm ultraviolet ray, and the yield of itis 16%.

Example 6

Except further adding 1,3,5-tribromobenzene (1.25 mmol) besidesparadibromobenzene (1.18 g, 5.0 mmol) and metadibromobenzene (4.72 g, 20mmol), by the same condition to the synthesis of P2/8-3 in Example 1(but polymerization time is 20 hours) polymerization reaction is carriedout and obtained polymer compound by 70% yield. This polymer compound isalso soluble in N,N′-dimethylformamide, chloroform and tetrahydrofuran.The molecular weight of this polymer is confirmed as 21000 by lightscattering method (measured in N,N′-dimethylformamide).

Example 7

10 mg of polymer compound obtained in Example 5 is dissolved in 5 mL ofdimethylformamide, and 20 μL of the solution is collected, coated on aplatinum electrode of 1 cm×1 cm and air dried. The yellowish thin filmof polymer obtained as above is dipped into acetonitrile containing0.10M of (NEt₄)BF₄ and the voltage of oxidation side is impressed. Atthis time, an oxidation peak of polymer is observed at 1.6V againstAg⁺/Ag, after that the polymer film becomes insoluble in solvent. It iswell-known that the alomatic compound causes coupling reaction(formula 1) by electrode oxidation [for example, refer to New PolymerExperiment Vol.3, “Synthesis and Reaction of Polymer” 334 page (KyoritsuShuppan, 1996)].

By the bridging reaction of schema 10 mentioned below, theinsolubirizing is caused.

By this insolubirization, the color of the polymer film is changed toblack. When the reduction side voltage is impressed to this blackcolored film, the reduction peaks appear at 0.85V and −1.4V againstAg⁺/Ag, and at the each step, the color of polymer film is changed tobrown, yellow. That is, it can be used as an elecrochromic unit.

Example 8

Film Shape Carbon Material

Polymers of P1/9 and P2/8-3 are dissolved in tetrahydrofuran, saidsolution is divided to 4 parts and dropped on a glassy carbon substrateof 14 mm×14 mm by four times and a cast film is prepared. The obtainedfilm is vacuumed in a desiccator and dried in the room temperature. Theweight of the polymer film of P1/9 and P2/8-3 measured from weightincreasing are respectively 29.7 mg and 23.1 mg.

These films are heated by elevating the temperature to 1000° C. by 1° C./min temperature elevating rate and maintaining 1000° C. for 1 hour.Then the temperature is cooled down to the room temperature by 2° C./mintemperature cooling rate. This is a previous calcination process. As themain calcinations process, the film is heated to 1200° C. by 1° C./mintemperature elevating rate under argon gas flow, then the temperature iselevated to 3000° C. by 5° C./min temperature elevating rate andmaintain this temperature for 30 minutes. After that, the temperature iscooled down to 1200° C. by 10° C./min temperature cooling speed, furthercooled down naturally. In both P1/9 and P2/8-3 cases, a graphitizatedcarbon thin film can be obtained.

INDUSTRIAL APPLICABILITY

As mentioned above, polyphenylene co-condensed polymer has a possibilityto be formed from solution, and can provide the expected function andeffect for the formation of an electrochromic of fluorescent body, as aforming material for carbonized film material and as a blue coloremission fluorescent material.

1. A polymer compound substantially comprising of an unsubstitutedparaphenylene group and an unsubstituted metaphenylene group, whereinthe ratio of the metaphenylene group to the polymer compound is from 60to 95%.
 2. The polymer compound of claim 1, wherein said polymercompound is soluble in organic solvent.
 3. The polymer compound of claim1, wherein the molecular weight of said polymer compound is in the limitof from 600 to
 40000. 4. The polymer compound of claim 2, wherein themolecular weight of said polymer compound is in the limit of from 600 to40000.